RE: [PATCH net-next 1/2] cxgb4/cxgb4vf: Add support for ndo_set_vf_vlan

quoted

Are you preventing VGT configuration once VST is configured?
If not, what to prevent VM user from configuring vlan interfaces on
top of the VF, even if VST is configured?

Again this misses documentation, what if VLAN interface is already configured in
VM before VST is configured.
Before there were callbacks to add/remove vlan interface, now that is removed
how to achieve it?
    OR
am I missing something?

I can only offer what our drivers [bnx2x, qed*] are doing - 
  -  VST is achieved by FW adding the vlan tag [unknowingly to VF] on egress traffic,
and silently stripping the vlan tag from the incoming traffic [so VF driver never
sees the tag].
  - Once VST is enabled, device [well, actually PF driver] would reject any further
requests for configuring VGT.
  - Once VST is configured, device would silently drop any vlan-tagged egress
Traffic sent  by VF, and would classify incoming traffic for that VF only if it's
tagged with the VGT vlan-id.
This has the effect of making existing vlan-interface over the VF completely
dysfunctional [as all transmissions from them would be dropped and they'll
never see any additional incoming traffic].